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81.
Measurement of aortic blood flow by Doppler echocardiography: day to day variability in normal subjects and applicability in clinical research 总被引:2,自引:0,他引:2
L Moulinier T Venet N B Schiller T W Kurtz R C Morris A Sebastian 《Journal of the American College of Cardiology》1991,17(6):1326-1333
To assess the reliability of Doppler ultrasound for detecting serial changes in cardiac output in response to experimental interventions, the day to day variability of the minute distance of aortic flow was determined in seven normal subjects maintained in a tightly controlled environment with regard to diet and activities. Measurements were made at the same time on 5 to 6 sequential days from an apical window with use of both continuous wave and pulsed wave Doppler techniques. Two statistical measures of reliability were calculated, the intraclass coefficient of correlation (R), which varies between 0 (null reliability) and +1 (perfect reliability), and the 95% confidence interval for the error-free value of a single measurement. For sequential measurements of arterial pressure, 24 h urinary volume and sodium excretion and body weight, the intraclass coefficients of correlation ranged from 0.85 to 0.99, indicating low day to day variability consistent with tight environmental control. Continuous and pulsed wave modes were proved equally and highly reliable for measuring minute distance of aortic flow. However, continuous wave Doppler ultrasound provided acceptable signals more frequently than did the pulsed wave technique. For continuous wave Doppler ultrasound, R was 0.87 (p less than 0.00001); the 95% confidence interval was +/- 1.81 m/min (or 11% of the mean of all measurements), which indicates that this method can be used in a single individual to detect a greater than 11% change in minute distance measured once before and after an intervention.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
82.
83.
In this study we have examined the correlation between activity of erythropoiesis and serum concentrations of erythropoietin and insulin-like growth factor I in male and female rats during accelerated growth (day 30-90). We found that fractional incorporation of iron into newly formed red blood cells was linearily correlated with body weight gain. Total iron incorporation into newly formed red blood cells reflecting total daily red cell formation increased almost linearily between day 25 and 80 after birth in both sexes. While serum erythropoietin concentrations decreased in the time interval investigated (25-120 days), serum IGF-I levels increased in both sexes between day 25 and 55. In this period, individual values of total iron incorporation into red blood cells and serum IGF-I concentrations were linearily correlated. Our observations support the concept that IGF-I rather than erythropoietin modulates erythropoiesis during accelerated growth and thus manages a proportional increase in body mass and oxygen transport capacity. 相似文献
84.
Kurtz SP 《AIDS and behavior》2005,9(1):63-72
Miami, Florida was at the vanguard of the rise of circuit parties and attendant club drug use—especially ecstasy, GHB, and ketamine—in the 1990s. Crystal methamphetamine, a drug of abuse among gay men for some years on the West coast, gradually moved east toward the end of the decade and recently became prevalent in Miami. This paper reports the results of focus group research into the motivations and consequences of crystal use among gay men in this new setting. Loneliness, fears about physical attractiveness due to aging and illness, and desires to lose sexual inhibitions were common motivations for using the drug. Continued use of crystal was often described as the cause of lost friendships, employment and long-term relationships, as well as sexual behaviors that put men at risk for HIV and other sexually transmitted infections. Implications for drug and sexual risk prevention interventions are discussed. 相似文献
85.
Smita S. Iyer Donald R. Latner Michael J. Zilliox Megan McCausland Rama S. Akondy Pablo Penaloza‐MacMaster Jeffrey Scott Hale Lilin Ye Ata‐Ur‐Rasheed Mohammed Tomoyuki Yamaguchi Shimon Sakaguchi Rama R. Amara Rafi Ahmed 《European journal of immunology》2013,43(12):3219-3232
CD4+ T follicular helper (TFH) cells are central for generation of long‐term B‐cell immunity. A defining phenotypic attribute of TFH cells is the expression of the chemokine R CXCR5, and TFH cells are typically identified by co‐expression of CXCR5 together with other markers such as PD‐1, ICOS, and Bcl‐6. Herein, we report high‐level expression of the nutrient transporter folate R 4 (FR4) on TFH cells in acute viral infection. Distinct from the expression profile of conventional TFH markers, FR4 was highly expressed by naive CD4+ T cells, was downregulated after activation and subsequently re‐expressed on TFH cells. Furthermore, FR4 expression was maintained, albeit at lower levels, on memory TFH cells. Comparative gene expression profiling of FR4hi versus FR4lo Ag‐specific CD4+ effector T cells revealed a molecular signature consistent with TFH and TH1 subsets, respectively. Interestingly, genes involved in the purine metabolic pathway, including the ecto‐enzyme CD73, were enriched in TFH cells compared with TH1 cells, and phenotypic analysis confirmed expression of CD73 on TFH cells. As there is now considerable interest in developing vaccines that would induce optimal TFH cell responses, the identification of two novel cell surface markers should be useful in characterization and identification of TFH cells following vaccination and infection. 相似文献
86.
Kurtz Patricia F. Strohmeier Craig W. Becraft Jessica L. Chin Michelle D. 《Journal of autism and developmental disorders》2021,51(8):2852-2865
Journal of Autism and Developmental Disorders - When individuals with autism and intellectual and developmental disabilities exhibit severe problem behavior, assessment and treatment are often... 相似文献
87.
Lia Burkhardt Frederic Bachmann Malte Mader Katharina Grupp Till Eichenauer Andreas Becker Meike Adam Markus Graefen Hartwig Huland Stefan Kurtz Stefan Steurer Maria C Tsourlakis Sarah Minner Uwe Michl Thorsten Schlomm Guido Sauter Hüseyin Sirma 《The Journal of pathology》2013,231(1):130-141
Deletion of 3p13 has been reported from about 20% of prostate cancers. The clinical significance of this alteration and the tumour suppressor gene(s) driving the deletion remain to be identified. We have mapped the 3p13 deletion locus using SNP array analysis and performed fluorescence in situ hybridization (FISH) analysis to search for associations between 3p13 deletion, prostate cancer phenotype and patient prognosis in a tissue microarray containing more than 3200 prostate cancers. SNP array analysis of 72 prostate cancers revealed a small deletion at 3p13 in 14 (19%) of the tumours, including the putative tumour suppressors FOXP1, RYBP and SHQ1. FISH analysis using FOXP1‐specific probes revealed deletions in 16.5% and translocations in 1.2% of 1828 interpretable cancers. 3p13 deletions were linked to adverse features of prostate cancer, including advanced stage (p < 0.0001), high Gleason grade (p = 0.0125), and early PSA recurrence (p = 0.0015). In addition, 3p13 deletions were linked to ERG+ cancers and to PTEN deletions (p < 0.0001 each). A subset analysis of ERG+ tumours revealed that 3p13 deletions occurred independently from PTEN deletions (p = 0.3126), identifying tumours with 3p13 deletion as a distinct molecular subset of ERG+ cancers. mRNA expression analysis confirmed that all 3p13 genes were down regulated by the deletion. Ectopic over‐expression of FOXP1, RYBP and SHQ1 resulted in decreased colony‐formation capabilities, corroborating a tumour suppressor function for all three genes. In summary, our data show that deletion of 3p13 defines a distinct and aggressive molecular subset of ERG+ prostate cancers, which is possibly driven by inactivation of multiple tumour suppressors. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
88.
Objective
The objectives of this paper are to discuss the results of a workshop conducted at EACH 2012. Specifically, we will (1) examine the link between communication, clinical reasoning, and medical problem solving, (2) explore strategies for (a) integrating clinical reasoning, medical problem solving, and content from the broader curriculum into clinical communication teaching and (b) integrating communication into the broader curriculum, and (3) discuss benefits gained from such integration.Methods
Salient features from the workshop were recorded and will be presented here, as well as a case example to illustrate important connections between clinical communication and clinical reasoning.Results
Potential links between clinical communication, clinical reasoning, and medical problem solving as well as strategies to integrate clinical communication teaching and the broader curricula in human and veterinary medicine are enumerated.Conclusion
Participants expressed enthusiasm and keen interest in integration of clinical communication teaching and clinical reasoning during this workshop, came to the idea of the interdependence of these skills easily, and embraced the rationale immediately.Practice implications
Valuing the importance of communication as clinical skill and embracing the interdependence between communication and thought processes related to clinical reasoning and medical problem solving will be beneficial in teaching programs. 相似文献89.
Naturally arising CD25+CD4+ regulatory T cells play key roles in the maintenance of immunologic self-tolerance and negative control of various immune responses. The majority, if not all, of them are produced by the normal thymus as a functionally distinct T-cell subpopulation, and their generation is in part developmentally controlled. Genetic abnormality in the development and function of this population can indeed be a cause of autoimmune disease, immunopathology, and allergy in humans. This regulatory population can be exploited to prevent and treat autoimmune disease by strengthening and reestablishing immunologic self-tolerance. 相似文献
90.
Irit Davidson Irina Shkoda Natalia Golender Shimon Perk Katherine Lapin Yevgeny Khinich Alexander Panshin 《Virus genes》2013,46(2):255-263
H9N2 influenza viruses are isolated in Israel since 2000 and became endemic. From November 2006 to the beginning of 2012, many H9N2 viruses were identified, all belonged to the Asian G1-like lineage represented by A/qu/Hong Kong/G1/97 (H9N2). In the present study, 66 isolates were selected for their hemagglutinin gene characterization. Most H9N2 isolates were distributed between two main groups, identified as the 4th and 5th introductions. The 5th introduction, was represented by a compact cluster containing viruses isolated in 2011–2012; the 4th introduction was subdivided into two subgroups, A and B, each containing at least two clusters, which can be identified as A-1, A-2, B-1, and B2, respectively. Genetic analysis of the deduced HA proteins of viruses, belonging to the 4th and 5th introductions, revealed amino acid variations in 79 out of 542 positions. All isolates had typical low pathogenicity motifs at the hemagglutinin (HA) cleavage site. Most viruses had leucine at position 216 in a receptor binding pocket that enables the virus to bind successfully with the cellular receptors intrinsic to mammals, including humans. It was shown that the differences between the HA proteins of viruses used for vaccine production and local field isolates increased in parallel with the duration and intensity of vaccine use, illustrating the genetic diversity of the H9N2 viruses in Israel. 相似文献